Bug: Streaming using ActionController::Live with Apartment

Description

Whenever data are streamed by writing to response buffer from ActionController::Live, the Apartment::Tenant.current is reset back to the default tenant.

Reproduction

The project is setup with 2 tenants:

• development is the default tenant.
• test is always used when accessing the site (refer to config/initializers/apartment.rb:102)

Reproduction steps:

• Run server in local (example: rails s).
• Go to path /stream (example: http://localhost:3000/stream).

Expected result

• Every lines should be test.
• Apartment::Tenant.current keeps its current value.

Actual behaviour

• The first few lines show test tenant (first 11 lines on my machine).
• The rest shows the default development tenant.